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  <title>Fetch a single column from the next row of a result set</title>
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    <li>Fetch a single column from the next row of a result set</li>
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  <div id="layout-content"><div id="mysqli-result.fetch-column" class="refentry">
 <div class="refnamediv">
  <h1 class="refname">mysqli_result::fetch_column</h1>
  <h1 class="refname">mysqli_fetch_column</h1>
  <p class="verinfo">(PHP 8 &gt;= 8.1.0)</p><p class="refpurpose"><span class="refname">mysqli_result::fetch_column</span> -- <span class="refname">mysqli_fetch_column</span> &mdash; <span class="dc-title">Fetch a single column from the next row of a result set</span></p>

 </div>

 <div class="refsect1 description" id="refsect1-mysqli-result.fetch-column-description">
  <h3 class="title">说明</h3>
  <p class="para">面向对象风格</p>
  <div class="methodsynopsis dc-description">
   <span class="modifier">public</span> <span class="methodname"><strong>mysqli_result::fetch_column</strong></span>(<span class="methodparam"><span class="type">int</span> <code class="parameter">$column</code><span class="initializer"> = 0</span></span>): <span class="type"><span class="type">null</span>|<span class="type">int</span>|<span class="type">float</span>|<span class="type">string</span>|<span class="type"><span class="type false">false</span></span></span></div>

  <p class="para rdfs-comment">过程化风格</p>
  <div class="methodsynopsis dc-description"><span class="methodname"><strong>mysqli_fetch_column</strong></span>(<span class="methodparam"><span class="type"><a href="class.mysqli-result.html" class="type mysqli_result">mysqli_result</a></span> <code class="parameter">$result</code></span>, <span class="methodparam"><span class="type">int</span> <code class="parameter">$column</code><span class="initializer"> = 0</span></span>): <span class="type"><span class="type">null</span>|<span class="type">int</span>|<span class="type">float</span>|<span class="type">string</span>|<span class="type"><span class="type false">false</span></span></span></div>

  <p class="para rdfs-comment">
   Fetches one row of data from the result set and returns the 0-indexed column.
   Each subsequent call to this function will return the value from the next row
   within the result set, or <strong><code>false</code></strong> if there are no more rows.
  </p>
  <blockquote class="note"><p><strong class="note">注意</strong>: <span class="simpara">此函数将 NULL 字段设置为 PHP <strong><code>null</code></strong> 值。</span></p></blockquote>
 </div>


 <div class="refsect1 parameters" id="refsect1-mysqli-result.fetch-column-parameters">
  <h3 class="title">参数</h3>
  <p class="para">
   <dl>
    <dt>

<code class="parameter">result</code></dt>
<dd>
<p class="para">仅以过程化样式：由
<span class="function"><a href="mysqli.query.html" class="function">mysqli_query()</a></span>、<span class="function"><a href="mysqli.store-result.html" class="function">mysqli_store_result()</a></span>、
<span class="function"><a href="mysqli.use-result.html" class="function">mysqli_use_result()</a></span>、<span class="function"><a href="mysqli-stmt.get-result.html" class="function">mysqli_stmt_get_result()</a></span> 返回的 <span class="classname"><a href="class.mysqli-result.html" class="classname">mysqli_result</a></span> 对象。</p></dd>

    
     <dt>
<code class="parameter">column</code></dt>

     <dd>

      <p class="para">
       0-indexed number of the column you wish to retrieve from the row. If
       no value is supplied, the first column will be returned.
      </p>
     </dd>

    
   </dl>

  </p>
 </div>


 <div class="refsect1 returnvalues" id="refsect1-mysqli-result.fetch-column-returnvalues">
  <h3 class="title">返回值</h3>
  <p class="para">
   Returns a single column
   from the next row of a result set or <strong><code>false</code></strong> if there are no more rows.
  </p>
  <div class="warning"><strong class="warning">警告</strong>
   <p class="para">
    There is no way to return another column from the same row if you
    use this function to retrieve data.
   </p>
  </div>
 </div>


 <div class="refsect1 examples" id="refsect1-mysqli-result.fetch-column-examples">
  <h3 class="title">范例</h3>
  <div class="example" id="example-1524">
   <p><strong>示例 #1 <span class="methodname"><strong>mysqli_result::fetch_column()</strong></span> example</strong></p>
   <div class="example-contents"><p>面向对象风格</p></div>
   <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /><br />mysqli_report</span><span style="color: #007700">(</span><span style="color: #0000BB">MYSQLI_REPORT_ERROR&nbsp;</span><span style="color: #007700">|&nbsp;</span><span style="color: #0000BB">MYSQLI_REPORT_STRICT</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$mysqli&nbsp;</span><span style="color: #007700">=&nbsp;new&nbsp;</span><span style="color: #0000BB">mysqli</span><span style="color: #007700">(</span><span style="color: #DD0000">"localhost"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"my_user"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"my_password"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"world"</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">$query&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #DD0000">"SELECT&nbsp;CountryCode,&nbsp;Name&nbsp;FROM&nbsp;City&nbsp;ORDER&nbsp;BY&nbsp;ID&nbsp;DESC&nbsp;LIMIT&nbsp;5"</span><span style="color: #007700">;<br /><br /></span><span style="color: #0000BB">$result&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">$mysqli</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">query</span><span style="color: #007700">(</span><span style="color: #0000BB">$query</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">/*&nbsp;fetch&nbsp;a&nbsp;single&nbsp;value&nbsp;from&nbsp;the&nbsp;second&nbsp;column&nbsp;*/<br /></span><span style="color: #007700">while&nbsp;(</span><span style="color: #0000BB">$Name&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">$result</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">fetch_column</span><span style="color: #007700">(</span><span style="color: #0000BB">1</span><span style="color: #007700">))&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"%s\n"</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">$Name</span><span style="color: #007700">);<br />}</span>
</span>
</code></div>
   </div>

   <div class="example-contents"><p>过程化风格</p></div>
   <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /><br />mysqli_report</span><span style="color: #007700">(</span><span style="color: #0000BB">MYSQLI_REPORT_ERROR&nbsp;</span><span style="color: #007700">|&nbsp;</span><span style="color: #0000BB">MYSQLI_REPORT_STRICT</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$mysqli&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">mysqli_connect</span><span style="color: #007700">(</span><span style="color: #DD0000">"localhost"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"my_user"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"my_password"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"world"</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">$query&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #DD0000">"SELECT&nbsp;CountryCode,&nbsp;Name&nbsp;FROM&nbsp;City&nbsp;ORDER&nbsp;BY&nbsp;ID&nbsp;DESC&nbsp;LIMIT&nbsp;5"</span><span style="color: #007700">;<br /><br /></span><span style="color: #0000BB">$result&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">mysqli_query</span><span style="color: #007700">(</span><span style="color: #0000BB">$mysqli</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">$query</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">/*&nbsp;fetch&nbsp;a&nbsp;single&nbsp;value&nbsp;from&nbsp;the&nbsp;second&nbsp;column&nbsp;*/<br /></span><span style="color: #007700">while&nbsp;(</span><span style="color: #0000BB">$Name&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">mysqli_fetch_column</span><span style="color: #007700">(</span><span style="color: #0000BB">$result</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">1</span><span style="color: #007700">))&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"%s\n"</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">$Name</span><span style="color: #007700">);<br />}</span>
</span>
</code></div>
   </div>

   <div class="example-contents"><p>以上例程的输出类似于：</p></div>
   <div class="example-contents screen">
<div class="cdata"><pre>
Rafah
Nablus
Jabaliya
Hebron
Khan Yunis
</pre></div>
   </div>
  </div>
 </div>


 <div class="refsect1 seealso" id="refsect1-mysqli-result.fetch-column-seealso">
  <h3 class="title">参见</h3>
  <p class="para">
   <ul class="simplelist">
    <li class="member"><span class="function"><a href="mysqli-result.fetch-all.html" class="function" rel="rdfs-seeAlso">mysqli_fetch_all()</a> - Fetch all result rows as an associative array, a numeric array, or both</span></li>
    <li class="member"><span class="function"><a href="mysqli-result.fetch-array.html" class="function" rel="rdfs-seeAlso">mysqli_fetch_array()</a> - Fetch the next row of a result set as an associative, a numeric array, or both</span></li>
    <li class="member"><span class="function"><a href="mysqli-result.fetch-assoc.html" class="function" rel="rdfs-seeAlso">mysqli_fetch_assoc()</a> - Fetch the next row of a result set as an associative array</span></li>
    <li class="member"><span class="function"><a href="mysqli-result.fetch-object.html" class="function" rel="rdfs-seeAlso">mysqli_fetch_object()</a> - Fetch the next row of a result set as an object</span></li>
    <li class="member"><span class="function"><a href="mysqli-result.fetch-row.html" class="function" rel="rdfs-seeAlso">mysqli_fetch_row()</a> - Fetch the next row of a result set as an enumerated array</span></li>
    <li class="member"><span class="function"><a href="mysqli-result.data-seek.html" class="function" rel="rdfs-seeAlso">mysqli_data_seek()</a> - Adjusts the result pointer to an arbitrary row in the result</span></li>
   </ul>
  </p>
 </div>


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